Gas Boiler v ASHP for Underfloor Heating

Fyne

New build bungalow and we are looking for an underfloor heating system, initial thought was ASHP, now wondering if a gas boiler would do the job cheaper and be easier to source a qualified tradesman. Has anyone used a gas boiler for underfloor heating, appreciate any thoughts on this subject.

daveyjp

My parents have a normal combi gas boiler with UFH in a bungalow.

It was installed as part of a significant refurbishment and cost no more than a traditional radiator system. 

The only downside is you need to have either hard floors or UFH specific carpet, which isn't as luxurious as traditional carpet.

Flight3287462

You should give serious consideration to future proofing your house especially if you are likely to be in it in 10 years time.

I prefer GSHP.  We have had it for 11 years (we built the house with good insulation) and it has been fabulous (if installed and specced properly.  GSHP also have a higher COP but is more expensive.

Having said all that gas is probably still the cheapest but for how long.

Verdigris

If you are also incorporating solar PV then an ASHP will make good use of spare "free" electricity.

Reed_Richards

Underfloor heating requires only warm rather than hot water.  So you should perhaps consider a gas boiler specifically designed to run at low temperatures as the possible alternative to a heat pump.  Have a look at this page: https://www.heatgeek.com/benefits-of-low-temprature-heating-systems/

matelodave

Verdigris said:

If you are also incorporating solar PV then an ASHP will make good use of spare "free" electricity.

I'd seriously doubt that.

Most need heating in the winter when it's ever so cold, the days are short and the sun doesn't shine very much meaning that solar panels will contribute very little to help heat the place. 

ProDave

matelodave said:

Verdigris said:

If you are also incorporating solar PV then an ASHP will make good use of spare "free" electricity.

I'd seriously doubt that.

Most need heating in the winter when it's ever so cold, the days are short and the sun doesn't shine very much meaning that solar panels will contribute very little to help heat the place. 

Oh yes it does.

Don't forget DHW heating.  With an ASHP you have a hot water cylinder, usually a large one.  By the simple act of setting the timer on my system so it only heats DHW from 11AM onwards, then there is a good chance that most of the DHW heating is done using up power generated by my solar PV.

I manage to self use almost all the PV we generate and in a year the PV generates more than the heating uses in the winter.

Fyne

Flight3287462 said:

You should give serious consideration to future proofing your house especially if you are likely to be in it in 10 years time.

I prefer GSHP.  We have had it for 11 years (we built the house with good insulation) and it has been fabulous (if installed and specced properly.  GSHP also have a higher COP but is more expensive.

Having said all that gas is probably still the cheapest but for how long.

Thank you for your reply, unfortunately a GSHP is not an option as we do not have a large garden.

Fyne

Thanks for your comments, we would prefer the ASHP route, we'll keep trying to find someone who will do the job.

markin

The hot water demand can usually be taken care of by a standard tank and a 350 pound solar diverter, any extra used power would be off set by being far cheaper to install vs a heat pump, so I would discount that as a being a huge benifit.

Fyne

ProDave said:

matelodave said:

Verdigris said:

If you are also incorporating solar PV then an ASHP will make good use of spare "free" electricity.

I'd seriously doubt that.

Most need heating in the winter when it's ever so cold, the days are short and the sun doesn't shine very much meaning that solar panels will contribute very little to help heat the place. 

Oh yes it does.

Don't forget DHW heating.  With an ASHP you have a hot water cylinder, usually a large one.  By the simple act of setting the timer on my system so it only heats DHW from 11AM onwards, then there is a good chance that most of the DHW heating is done using up power generated by my solar PV.

I manage to self use almost all the PV we generate and in a year the PV generates more than the heating uses in the winter.

Interesting, what is the Kw of your solar PVs ?